brainpopfandomcom-20200223-history
Energy Sources/Transcript
Transcript Text reads: The Mysteries of Life with Tim and Moby Tim and Moby sitting on the ground by a campfire. Their tent is placed in the woods. It is dark outside. Tim is holding a piece of paper and Moby is holding a branch with several marshmallows on it. TIM: Dear Tim and Moby, where do we get the power to heat our homes, light up street lamps, and move cars? From Abby. The camera focuses on the letter that Tim is reading. TIM: Humans use energy for everything! As a result, we've come up with a lot of ways to generate it. The scene changes to show Tim sitting by the campfire addressing the camera. TIM: Probably the most basic method of energy production is from burning biomass, like wood and animal droppings. A piece of wood and a pile of animal droppings are shown. Word “biomass” comes up on the bottom of the screen. TIM: This campfire my dad built is a good example of biomass energy. The scene shows Tim sitting by the campfire. Moby is not shown but his branch with marshmallows is placed over the fire. TIM: Biomass energy is used all over the world for cooking, lighting, and heating. An animation shows a campfire. Three green symbols appear on the screen. The first symbol represents cooking and shows a saucepan. The second represents lighting and shows eight evenly spaced line segments, resembling a source of light. The last symbol has three curved lines showing steam; this symbol represents heating. TIM: Now, if you're talking about electricity, there are lots of ways to generate that. Tim addresses the camera. TIM: Most involve a device called a generator. An image labeled “generator” shows an object that consists of three parts. The top part is cylindrical in shape and orange in color. It is connected to another cylinder by a steel rod. TIM: Generators come in tons of shapes and sizes, but essentially, they all do the same thing: convert motion into electricity. Here's the basic principle: If you rotate a coil between the poles of a magnet, an electric current flows through the coil as it passes through the magnetic field. An animation first adds a wire running from the generator to a socket and then removes the orange cylindrical part of the generator to show its inner structure. A rectangular coil is now visible. A U-shaped magnet is then placed around the coil. A magnetic field is shown by several curved dashed lines connecting the two ends of the magnet. An animation then shows the coil spinning. An indicator light above the electrical socket glows yellow. MOBY: --Beep? The scene changes to show Moby. He is holding his right hand up with his index pointing and rotating in a clockwise direction. TIM: Good question. Finding the energy to turn the coils is the real trick. Here are some ways to do it. Water powered, or hydroelectric, power units use water trapped by reservoirs and dams to generate energy. The scene changes to show an aerial view of a dam. On screen text reads: hydroelectric power. TIM: Water flowing through a small opening in a dam can turn a wheel called a turbine, which is attached to the generator. An animated diagram shows the structure of a dam. An opening in dam’s wall is letting the water escape. Flowing water is turning a turbine close to the opening of the wall. The spinning turbine is circled with a dotted line that connects it to another dotted circle that shows the generator also spinning. The word “turbine” appears on the screen. TIM: This can also be accomplished by using the ocean's tides. An animation shows a structure in the face of a cliff. A wall with a turbine in its opening is shown. The water level starts to increase, eventually filling the reservoir through the opening. TIM: At high tide, water is trapped in a reservoir. At low tide, the water is released, turning turbines. Once the water level reaches the highest point, the opening is closed and remains closed until the water level on the outside falls below the point where the turbine is located. The trapped water is then released, spinning the turbine. The spinning turbine is circled with a dotted line that connects it to another dotted circle that shows the generator also spinning. The phrase “tidal power” appears on the screen. TIM: Windmills work in a way similar to hydroelectric plants, using energy provided by the wind. The scene changes to show a green field with several windmills. All of the windmills are spinning at the same rate and in the same direction. A spinning generator is then shown. TIM: Both wind and water energy are often also used to create mechanical energy, turning gears to pump oil or water out of the ground, or to grind stuff up, or anything, really. Tim addresses the camera. Three green symbols appear on the screen. The first symbol is an oil derrick. The second symbol is a drop of water. The third symbol is two circular gears grinding objects. TIM: Geothermal energy comes from hot rocks in the earth’s crust that hold temperatures up to 1,000 degrees Celsius. Water heated by these rocks turns to steam, which turns the turbines of generators. A U-shaped pipe running through the Earth’s crust is shown. The rocks are shown to be different shapes and are orange and black on color. An animation then shows water running through the pipe. Water turning into steam is shown by changing the color of the water from blue to white. A dotted circle with a spinning generator appears on the screen. The phrase “geothermal energy” is placed on the bottom of the screen. TIM: Solar energy comes from the sun. The scene changes to show the sun. The phrase “solar energy” is placed on the bottom of the screen. TIM: Heat from the sun can be focused onto water, creating steam, which turns the turbine of a generator. The scene changes to show the sun in the top right corner of the screen. An animation shows an arrow leaving the sun and getting deflected off a mirror and hitting a pipe. The mirrors are arranged so that they are parallel to the pipe. A dotted circle with a spinning generator appears on the screen. The phrase “solar energy” is placed on the bottom of the screen. TIM: Solar energy can be also be converted directly into electricity with the use of a photovoltaic cell. The scene changes to show four green rectangles placed side by side. Once the camera zooms out it is clear that the four rectangles are the photovoltaic cell of a calculator, which is located right above its display. Phrase “photovoltaic cell” is placed on the bottom of the screen. TIM: Nuclear reactors take advantage of the unstable atoms in substances like uranium and plutonium. An image shows nuclear reactor buildings. The phrase “nuclear power” is placed at the top of the screen. TIM: A process called nuclear fission splits the nuclei of these atoms, nuclear fission creating a controlled chain reaction and generating a lot of heat. An animation shows one yellow sphere hitting a cluster composed of yellow and blue spheres and breaking the cluster up into several smaller clusters and individual spheres. An animation then shows the same process but with several clusters shown on the screen. The first collision causes another, setting off a chain reaction. MOBY: --Beep! TIM: You guessed it! The camera focuses on Moby. TIM: The heat turns water into steam, which turns the turbines of generators. A spinning generator appears on the screen. TIM: Then we have fossil fuels. Tim addresses the camera while sitting by the campfire. The phrase “fossil fuels” comes up on the screen. TIM: As their name suggests, fossil fuels like coal, oil, and natural gas, come from the remains of dead animal and plant matter. The screen is black at first but then several images pop up one after another. First an image of coal is shown. An image of oil, shown as a small black puddle, is placed next to it. Natural gas is shown as a yellow cloud. Remains of dead animals and plant matter are shown with the corpse of a dinosaur and a tree trunk lying on top of it. TIM: Fossil fuels are burned, turning water into steam, turning turbines. An image of a factory with black smoke coming out of its smoke stacks is shown. A dotted circle with a spinning generator appears on the screen. TIM: A couple of problems with fossil fuels: First, burning them produces a lot of pollution, as well as carbon dioxide, which contributes to global warming. An animation shows clouds of black smoke rising up. TIM: Second, the process that turns a tree into a fossil fuel takes millions of years, much longer than it takes us to burn it. An animation shows a tree fall and slowly become one with the ground. The ground level goes up and a new layer, gray in color, is formed. TIM: At our present rate of consumption, it’s not a question of whether we’ll run out of fossil fuels, it’s just a matter of when. An animation shows an excavator arm taking something in the shape of a boulder out of the ground. The substance quickly burns up and turns into ash. TIM: Some say it could happen in the next few centuries. That’s why scientists and industries are working hard to develop alternate energy sources, like fuel cells, for example. Tim addresses the camera. The phrase “fuel cells” is placed on the bottom of the screen. TIM: Fuel cells convert hydrogen and oxygen into water, producing electricity in the process. An image of a fuel cell is shown. Hydrogen and oxygen entering the device is shown as two circles labeled Upper H and Upper O entering on one side. A similar circle with lightning drawn on it then leaves the fuel cell, representing electricity. TIM: The only by-products of the reaction are heat and water. Heat and water by-products are shown by two circles, one with curved lines drawn on it and the other one showing a drop of water. TIM: The kinks are still being worked out, but hopefully, alternative energy sources will bring us closer to safe, clean energy sources that humans need so badly. The scene changes to show Tim address the camera while sitting by the campfire. Moby’s branch with marshmallows catches on fire. Tim looks surprised. Moby gets a fire extinguisher and puts out the campfire. The screen goes black and remains dark. TIM: Now you've done it. MOBY: Beep. The lights on Moby’s chest flash in the dark. TIM: Dad, the fire, uh, went out! Hey, pass me a marshmallow? Tim eats the fired marshmallow. TIM: I meant a fresh one! Category:BrainPOP Transcripts Category:BrainPOP Science Transcripts Category:BrainPOP Engineering & Technology Transcripts